1. Field of the Invention
The present invention relates to a flip-up type seat having a seat member swingable between its seated position where it is kept substantially horizontal and its flipped-up position where it is kept substantially vertical.
2. Description of the Related Art
The flip-up type seats of this kind have been used as those for student desks in schools, those in conference rooms, theaters and stadiums, those for various kinds of works such as drawing, those in street-cars, buses and commuters' trains and those for public at stations and parks.
In the conventional flip-up type seats, the seat member is swung around its rear end between its seated position where it is kept substantially horizontal in relation to its seat supports such as legs and its flipped-up position where it is kept substantially vertical in relation to them.
FIGS. 11 and 12 show a conventional flip-up type seat applied to a student desk with a seat. Reference numeral 1 denotes a plurality of narrow student desks arranged at certain intervals in a back and forth directions on a floor in a class room. FIG. 11 shows a flat floor, and FIG. 12 shows a stepped floor.
Each of the student desks includes a plurality of legs 2 fixed on the floor and extended upward and a desk top 3 horizontally attached to the tops of the legs 2. Each of the student desks 1 excepting on the first line is provided with a flip-up type seat 4 for use by a student in a front line.
Each flip-up type seat 4 is constructed by a pair of right and left brackets 5 fixed to and projected forward from vertical middle portions of a pair of legs 2 adjacent each other in the plural legs 2 of the student desk 1 on the second, third, . . . x-th lines, a pair of right and left seat member support arms 7 swingably supported at their rear end portions by a shaft 6 which is supported horizontal by the paired right and left brackets 5, and a seat member 8 supported by the paired right and left seat member support arms 7. At positions above the paired right and left bracket 5, a seat back 9 is further attached to a pair of legs 2 adjacent to each other in the plural legs 2 of the student desk 1 on each of the second, third, . . . x-th line.
In the conventional flip-up type seat 4 having the above-described arrangement, the seat member 8 is located at its flipped-up position where it is swung vertical above the shaft 6, when the seat member 8 is not used. When the user wants to use the seat member 8, the seat member 8 is swung downward around the shaft 6 from its flipped-up position to its seated position where it is kept substantially horizontal.
In most of the conventional flip-up type seats, a twisted coil spring (not shown) is attached to the shaft 6. The seat member 8 is therefore automatically forced from its seated position to its flipped-up position by the twisted coil spring when the seat member 8 is not used.
In order to swing the seat member 8 around the shaft 6 from its flipped-up position to its seated position when the user wants to use the seat member 8, the user must push the seat member 8 downward by his or her own hand or buttocks. When the user uses his or her own hand to swing the seat member 8 from its flipped-up position to its seated position, the user must take half-sitting pose with bending his or her waist or legs. When the user uses his own buttocks, the user must put his or her buttocks on the upward directed front end surface of the seat member 8 which has been flipped up, then sit down while moving his buttocks downward, and further then move backward his or her buttocks on the seat member 8 as the seat member 8 comes nearer its seated position. This is a quite complicated action.
When the user stands up from his or her sitting pose on the seat member 8, the user must use his or her own hand or allow the urging means to swing the seat member 8 from its seated position to its flipped-up position, while keeping his or her half-sitting pose.
The user must take unstable half-sitting pose in either case to swing the seat member 8 between its flipped-up position and its seated position.
In the case of the conventional flip-up type seat 4, the distance B between the rear end of the desk top 3 and the front end of the seat member 8 which is on the way of its being swung is so set as not to catch his or her thighs or body between them while the user is taking half-sitting pose. This distance B thus set limits the size A of the seat member 8 in its back and forth directions. The limited size A does not give the user enough relaxation and comfort on the seat member 8.
In the case of the flip-up type seats 4 having constructions which are obtained by removing the desk tops 3 from the student desks 1, and used in the theater, the user must stand up completely and swing the seat member 8 from its seated position to its flipped-up position so as to allow a person to pass through between the user and the seat 4 on the front line.
The conventional flip-up type seat 4 is sometimes used while leaving its seat member 8 flipped-up. In this case, the user lightly puts his or her buttocks on the upward directed front end surface of the seat member 8 which has been flipped up. However, the front end surface of the seat member 8 has so small an area as to make him or her feel pain at his or her buttocks. In addition, the user's clothes are liable to be soiled and broken by the lower surface of the seat member 8 and the seat support arms 7, which are directed forward when it is flipped up.
Further, the upper surface of the seat member 8 is directed backward when the seat member 8 is left flipped-up. In the class room where the floor is stepped as shown in FIG. 12, therefore, the upper surface of the seat member 8 is liable to be soiled by shoes of an user seated on the seat member 8 of the flip-up type seat 4 on the back line.